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From: Alan Modra <amodra@gmail.com>
To: binutils@sourceware.org
Subject: ubsan: tc-z80.c:3656 shift exponent 32 is too large
Date: Wed,  2 Sep 2020 18:12:55 +0930	[thread overview]
Message-ID: <20200902084302.26786-12-amodra@gmail.com> (raw)

	* config/tc-z80.c (is_overflow): Avoid too large shift.

diff --git a/gas/config/tc-z80.c b/gas/config/tc-z80.c
index 45fcd6fbf7..2e17d00552 100644
--- a/gas/config/tc-z80.c
+++ b/gas/config/tc-z80.c
@@ -3653,7 +3653,7 @@ md_assemble (char *str)
 static int
 is_overflow (long value, unsigned bitsize)
 {
-  long fieldmask = (1UL << bitsize) - 1;
+  long fieldmask = (2UL << (bitsize - 1)) - 1;
   long signmask = ~fieldmask;
   long a = value & fieldmask;
   long ss = a & signmask;
-- 
Alan Modra
Australia Development Lab, IBM


                 reply	other threads:[~2020-09-02  8:44 UTC|newest]

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